Question 1
Question
The Na+/K+ pump is:
Question 2
Question
The Na+/K+ pump is found:
Answer
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a) in all types of cells;
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b) in the excitable cells only;
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c) in the human excitable cells.
Question 3
Question
The Na+/K+ pump is a type of:
Answer
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a) passive ion transporter;
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b) facilitated ion channel;
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c) active ion transporter.
Question 4
Question
Does the Na+/K+ pump require an energy source?
Answer
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a) yes, it hydrolyses adenosine triphosphate;
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b) no, ions are driven by concentration gradients;
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c) yes, it uses redox reactions in the annular lipid molecules.
Question 5
Question
What are the operation modes of the Na+/K+ pump?
Question 6
Question
Describe the directions of ion transport through the Na+/K+ pump:
Answer
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a) moves Na+ and K+ ions out of the cell;
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b) moves Na+ out, and K+ in;
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c) moves Na+ in, and K+ out.
Question 7
Question
. The Na+/K+ pump is found in:
Question 8
Question
Which of the following transport processes is considered an active transport?
Answer
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a) the transfer of substance (molecules, ions) from area with high concentration into area of lower concentration;
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b) the transfer of substance (molecules, ions) irregardless of the direction of the concentration gradient;
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c) the transfer of substance (molecules, ions) from area with low concentration into area of higher concentration;
Question 9
Question
According the type of energy supply, the active membrane transport is divided into:
Question 10
Question
Which of the following statements does not hold for primary active transport?
Question 11
Question
In the electrogenic regime the sodium – potassiumpump:
Answer
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a) moves one negative charge out of the cell;
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b) moves one positive charge out of the cell;
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c) moves three positive charges in, for two positive charges out.
Question 12
Question
Which of the following statements refer to the primary active transmembrane transport?
Answer
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a) transport of organic molecules;
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b) uses the energy of the concentration gradient of Na+;
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c) involves the active transport of: Na+, K+, Ca2+, H+, Mg2+, Cl-, and bicarbonate ions.
Question 13
Question
The secondary active transport is carried through:
Answer
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a) membrane protein carriers;
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b) transmembrane ion channels;
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c) spontaneously formed (and vanishing) membrane pores.
Question 14
Question
The Na+/I- symporter, which transports iodine into the thyroid gland, cannot distinguish between non-radioactive (I-127) and radioactive (I-131) iodine. How could this be explained?
Answer
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a) radioactive and non-radioactive iodine have the same physical properties;
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b) radioactive and non-radioactive iodine have the same number of neutrons;
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c) radioactive and non-radioactive iodine have the same chemical properties.
Question 15
Question
What type of membrane transport delivers iodide into the thyroid gland?
a) passive transport;
Question 16
Question
What is the direct driving force for the transmembrane transport of iodide?
Answer
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a) energy from the hydrolysis of ATP;
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b) the electrochemical gradient of Na+ ions;
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c) the concentration gradient of Na+ ions.
Question 17
Question
Antiport is defined as:
Answer
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a) coupled membrane transport, where substances move in the same direction;
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b) coupled membrane transport, where substances move in opposite directions;
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c) ion channel that allows ions to move only in one direction.
Question 18
Question
The operational mode of the thyroid Na+/I- symporter is as follows:
Answer
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a) 2 Na+ ions move in, for each I- ion moving in;
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b) 2 Na+ ions move out, for each I- ion moving in;
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c) 3 Na+ ions move in, for 2 I- ions moving out.
Question 19
Question
An example for secondary active transport is:
Answer
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a) the Ca2+ pump;
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b) the Na+/I- symporter;
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c) the K+ leak channel.
Question 20
Question
The electrogenic mode of operation of the Na+/K+ pump is as follows:
Answer
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a) 2 Na+ ions move out, for 3 K+ ions moving in;
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b) 3 Na+ ions move out, for 2 K+ ions moving in;
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c) 3 Na+ ions move in, for 2 K+ moving out;
Question 21
Question
Transmembrane transport of substances against their electrochemical gradient, that does not use direct coupling of ATP is called:
Question 22
Question
When substances are transported across the membrane through specialised protein molecules, the process is described as:
Question 23
Question
When substances use protein carrier molecules to cross the membrane, the process is described as:
Question 24
Question
What type of membrane transport involves the accumulation of iodine in the follicular cells of the thyroid gland?
Answer
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b) secondary-active;
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c) facilitated passive.
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a) primary-active;
Question 25
Question
The primary active membrane transport is carried by:
Answer
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a) aquaporins;
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b) ion channels;
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c) ion pumps.
Question 26
Question
The bi-directional secondary active transport is called:
Answer
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a) simport;
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b) antiport;
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c) uniport.